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Stargazing I Am Cursed! Ack! Fi! My New Telescope hates me

  1. Aug 21, 2007 #1
    Step 1:take telescope out of box and assemble according to instructions.

    2. Install Crayford focuser.

    3. Collimate to the best of my ability/knowledge

    4. Take scope outside and point at Jupiter

    5. Become enfuriated because for the 2nd night in a row, all I have been able to see is a fuzzy @#$!ing disc with crosshairs over it....WHY CAN I SEE THE SPIDER VANES?!

    I going to go hit my head against the wall for awhile.

    Casey
     
  2. jcsd
  3. Aug 21, 2007 #2

    chroot

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    You can see the spider vanes in the eyepiece? :bugeye: This doesn't even sound like a collimation issue; it sounds more like something is installed completely incorrectly. How are you attempting to collimate it?

    - Warren
     
  4. Aug 21, 2007 #3

    turbo

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    OK. Let's try this. Take your scope outside in the daytime, and look at a distant object. If you cannot bring it into focus, adjust the position of the primary until you can see it (a distant tree-line should do). Then, without racking the position of the primary in or out, tweak the primary screws to get the mirror colimnated with the secondary. This should get you close enough so you can see something on your next outing and get you motivated to tweak the alignment of your scope's mirrors so that you can see more.
     
  5. Aug 21, 2007 #4
    I know, but I can see them!

    I already took it out today and focused in on a blinking light about 1/4 of a mile away. I could see the vanes then too. I alligned the Primary and secondary with each other I think. I mean, I adjusted the 2ndary so that I could see all of the primary in it.

    Then I adjusted the tilt of the primary until the 'dot' on the sight tube was inside of the center-mark on the primary.
     
  6. Aug 22, 2007 #5

    russ_watters

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    I'm not sure about your collimation issues, but unless you are somewhere very south, Jupiter is going to be a fuzzy mess because it is so low on the horizon.
     
  7. Aug 22, 2007 #6
    Maybe I am just a D-bag. The Orion Tech guy insists that it must be diffraction spikes...so maybe I just don't know what I am doing yet... I am going to Google around and see if I can find a picture of what diffraction spikes would look like...
     
  8. Aug 22, 2007 #7

    chemisttree

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  9. Aug 22, 2007 #8
    I don't know. I have not had a good viewing night, but I think the spikes I was seeing were black. Thus, I thought they were the vanes?
     
  10. Aug 22, 2007 #9

    chroot

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    Can you... take some pictures of the inside of the scope for us? And let us take a look at how you've set up the critical pieces?

    Do you have an astronomy club nearby whom you could contact for in-person help?

    - Warren
     
  11. Aug 22, 2007 #10

    russ_watters

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    There is a star test for collimation - point at a medium-bright (it must not be very bright) star, use a high magnification, and see if the star makes concentric circles. Then slowly focus in and out and see if it makes big concentric circles when going out of focus. If the circles are not concentric, the collimation is off.
     
  12. Aug 22, 2007 #11
    I'll try that out. I did not set up the inner workings though. It came with the optical tube nearly complete. All I had to do was install the new focuser and the tube rings.
     
  13. Aug 22, 2007 #12
  14. Aug 22, 2007 #13

    russ_watters

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    Tough to tell, but it looks in the video like one of the supports for the secondary is twisted, making it face into the telescope. Make sure they present as small a cross-section as they can to the inside of the scope.
     
  15. Aug 22, 2007 #14

    turbo

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    Russ is right. It looks like the vanes of the spider are not parallel to the light path. That will cause problems. If so, you need to loosen the nuts fastening the spider to the tube, and make sure to re-tension them gently while making sure that the flats of the vanes are parallel to the tube.

    Then, make sure that your primary is aimed at your secondary, and fine-tune the secondary, if necessary, then tweak the primary again until your scope can do the inside-and-outside of focus star test. A star inside or outside of focus should present a nice symmetrical disk that resolves cleanly to a point at focus.
     
  16. Aug 22, 2007 #15

    chroot

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    Yeah, the spider vanes look to be in pretty bad shape. You might even have trouble centering the secondary over your primary with the vanes bent and twisted, which will pretty much prevent you from ever getting good collimation.

    - Warren
     
  17. Aug 22, 2007 #16
    Last edited: Aug 22, 2007
  18. Aug 22, 2007 #17

    russ_watters

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    I guess I would have thought they could rotate relatively easily. Do you have the screws too tight?
     
  19. Aug 22, 2007 #18
    I am not sure what "too" tight is. I mean, I think they are within reason. I was able to rotate them somewhat and then I held the vanes as parallel to the optical tube as possible and slowly tightened the four thumbscrews. The video in post#16 is what they look like now, after attempting to fix. It looks like an improvement, but I e-mailed Orion anyway to see what they would be willing to do.

    I don't want to pay to ship anything back, but if they are willing to just send me four new vanes (they look cheap enough) I could reinstall them. If not, I am sure I could fabricate some new ones.

    ~Casey
     
  20. Aug 23, 2007 #19

    Chronos

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    Agree with turbo, loosen the vane nuts while focused on a distant point light source, then slowly tighten them. You should not see the vanes, just diffraction spikes from off center light sources - and these should be subtle. If you can see the vanes, your secondary mirror is not at the proper distance from the primary. Do you have two sets of holes for the vanes? [one for prime plane photography and one for visual]
     
  21. Aug 23, 2007 #20
    I will check tomorrow. Like I said, the tube came assembled, so I am not sure. These "spikes" certainly are not subtle.

    Casey
     
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